Not so. I think the Instant Pot does very well at cooking rice of all kinds. I've used it for white rice (a 1-button operation with the "Rice" function), and with the right settings, found with some experimentation, have got excellent results with brown rice, wild rice, and "quick" (scarified) brown rice. You can certainly retire a standard rice cooker if you get an Instant Pot. (That said, I admit I don't know what a Zojirushi is capable of in cooking rice.)